Inertial Gas-Liquid Separator with Variable Flow Actuator

ABSTRACT

An inertial gas-liquid separator has a variable flow actuator movable to open and close a variable number of accelerating flow nozzles.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 10/946,603, filed Sep. 21, 2004.

BACKGROUND AND SUMMARY

The invention of the above noted parent application relates to inertialgas-liquid impactor separators for removing and coalescing liquidparticles from a gas-liquid stream, including in engine crankcaseventilation separation applications, including closed crankcaseventilation (CCV) and open crankcase ventilation (OCV).

Inertial gas-liquid separators are known in the prior art. Liquidparticles are removed from a gas-liquid stream by accelerating thestream or aerosol to high velocities through nozzles or orifices anddirecting same against an impactor, typically causing a sharpdirectional change, effecting the noted liquid separation. Such inertialimpactors have various uses, including in oil separation applicationsfor blow-by gases from the crankcase of an internal combustion engine.

The parent invention provides improvements in inertial gas-liquidimpactor separators, including variable flow.

The present invention arose during continuing development effortsrelating to the above noted parent invention.

BRIEF DESCRIPTION OF THE DRAWING Parent Application

FIG. 1 is a schematic sectional illustration of an inertial gas-liquidimpactor separator in accordance with the parent invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1.

FIG. 3 is a schematic perspective view of a portion of FIG. 1 butshowing another embodiment.

FIG. 4 is a schematic perspective view of a portion of FIG. 1 butshowing another embodiment. FIG. 5 is a perspective elevational view ofan inertial gas-liquid impactor separator incorporating the embodimentof FIG. 4.

FIG. 6 is a perspective view partially broken away of the constructionof FIG. 5.

FIG. 7 is a perspective view partially broken away of the constructionof FIG. 5.

FIG. 8 is an exploded perspective view of a portion of FIG. 5.

FIG. 9 is a sectional view of the construction of FIG. 5 showing a firstposition of the actuator.

FIG. 10 is like FIG. 9 and shows another position of the actuator.

FIG. 11 is a schematic perspective view of a portion of FIG. 1 butshowing another embodiment.

FIG. 12 is a schematic illustration of a portion of another inertialgas-liquid impactor separator in accordance with the parent invention.

FIG. 13 is a sectional view of an inertial gas-liquid impactor separatorincorporating the embodiment of FIG. 12.

FIG. 14 is like FIG. 13 and shows another position of the actuator.

FIG. 15 is a sectional view of the construction of FIG. 13.

FIG. 16 is a perspective view of the construction of FIG. 13.

FIG. 17 is an exploded perspective view of the construction of FIG. 16.

FIG. 18 is another exploded perspective view of the construction of FIG.16.

FIG. 19 is a schematic perspective view of a portion of another inertialgas-liquid impactor separator in accordance with the parent invention.

FIG. 20 is a sectional view of another embodiment of an inertialgas-liquid impactor separator in accordance with the parent invention.

FIG. 21 is a top elevation view taken along line 21-21 of FIG. 20.

FIG. 22 is an enlarged view of a portion of FIG. 20.

Present Application

FIG. 23 is a schematic sectional view of an inertial gas-liquidseparator in accordance with the present invention.

FIG. 24 is like FIG. 23 and shows another embodiment.

FIG. 25 is like FIG. 23 and shows another embodiment.

FIG. 26 is like FIG. 23 and shows another embodiment.

DETAILED DESCRIPTION Parent Application

FIG. 1 shows an inertial gas-liquid impactor separator 30 for coalescingand removing liquid particles from a gas-liquid stream 32, shown in anexemplary crankcase ventilation separation application for an internalcombustion engine 34. In such application, it is desired to vent blow-bygases from crankcase 36 of engine 34. Untreated, these gases containparticulate matter in the form of oil mist and soot. It is desirable tocontrol the concentration of the contaminants, especially if the blow-bygases are to be recirculated back to the engine's air intake system, forexample at air intake manifold 38. The oil mist droplets are generallyless than 5 μ in diameter, and hence are difficult to remove usingconventional fibrous filter media while at the same time maintaining lowflow resistance as the media collects and becomes saturated with oil andcontaminants.

Separator 30 includes a housing 40 having an inlet 42 for receivinggas-liquid stream 32 from engine crankcase 36, an outlet 44 fordischarging a gas stream 46 to air intake manifold 38, and a drain 45draining separated fluid at 47 from impactor collector 54 and returningcollected oil droplets at 47 to crankcase 36. Nozzle structure 48 in thehousing has a plurality of nozzles provided by orifices such as 50, 52,FIGS. 1, 2, receiving the gas-liquid stream at 58 from inlet 42 andaccelerating the gas-liquid stream through nozzles 50, 52. The pluralityof nozzles provides a cumulative flow in parallel therethrough. Aninertial impactor collector 54 in the housing is in the path of theaccelerated gas-liquid stream at 58 and causes liquid particleseparation by a sharp directional change as shown at 56. In thepreferred embodiment, impactor collector 54 has a rough porouscollection or impingement surface 60 causing liquid particle separationfrom the gas-liquid stream, and is like that shown in U.S. Pat. No.6,290,738, incorporated herein by reference. Nozzle orifices 50, 52 mayhave a venturi or frustoconical shape as in the incorporated '738patent.

A variable flow actuator 62 varies the cumulative flow through theplurality of nozzles in response to a given parameter. In one desirableembodiment, cumulative flow velocity is varied, though other flowcharacteristics may be varied. The gas-liquid stream flows axially alongan axial flow direction at 58 through orifices 50, 52. Actuator 62 ismovable along a given direction relative to the orifices to vary thenoted cumulative flow. In one embodiment, actuator 62 is moveable alongthe noted given direction relative to the orifices to vary the totalarea and hence the resultant flow velocity. In FIGS. 1, 2, actuator 62is a disk or plate movable across one or more of the orifices to changethe cross-sectional area thereof transverse to axial flow direction 58.Disk 62 is movable as shown at arrow 64 left-right in FIGS. 1, 2,transversely to axial flow direction 58. In the embodiment of FIGS. 1,2, disk 62 as a plurality of elongated slots or openings 66, 68 alignedwith respective nozzle orifices 50, 52 and transversely slidabletherealong to vary the size thereof available to axial flowtherethrough, and hence to vary the cumulative flow area. In a furtherembodiment, one or more of nozzle orifices 50, 52 may be closed oropened during movement of disk 62, to thus vary the number of orificesavailable to axial flow therethrough, to thus vary the noted cumulativeflow area. In a further embodiment, movement of actuator disk 62 variesboth the size and number of the orifices, for example movement ofactuator disk 62 back and forth along direction 64 may expand andrestrict the orifices along a cross-sectional area thereof transverse toflow direction 58, to vary the size of the orifices, and movement ofactuator disk 62 back and forth along direction 64 may open and closeother of the orifices, to vary the number of orifices through which thegas-liquid stream flows.

In one embodiment, the noted parameter to which variable flow actuator62 responds is pressure of the gas-liquid stream. Housing 40 includes apressure sensor 70 in the form of a diaphragm or membrane coupledthrough link 72 to actuator 62 to actuate the latter to move left-rightat 64 in FIGS. 1, 2. As the pressure of the gas-liquid stream increases,diaphragm 70 moves leftwardly in FIG. 1, which in preferred formincreases the size of orifices 50, 52, etc. (increases thecross-sectional flow area thereof) and/or increases the number oforifices 50, 52, etc. open to flow therethrough. The increasing pressureof the gas-liquid flow stream in housing chamber 74 overcomes the biasspring 76 to cause leftward movement of diaphragm 70. If the gas-liquidflow pressure decreases, then biasing spring 76 moves actuator disk 62rightwardly in FIG. 1, preferably to reduce the size and/or number oforifices 50, 52, etc. In this manner, a desired pressure differential ΔP(delta P) is maintained, eliminating the need to make compromisesbetween minimum and maximum flow rates, engine sizes, changingconditions such as engine wear, speed, braking, etc. The variable flowactuator maximizes efficiency by adapting to different engine sizes,flow ratings, and changing conditions during engine operation, andovercomes prior trade-offs required in a fixed flow separator. In theembodiment of FIG. 1, housing chamber 78 on the opposite side ofdiaphragm 70 from chamber 74 is vented to atmosphere as at vent openings80, 82, for referencing ΔP, though other reference pressures may beused.

FIG. 3 shows a further embodiment having an actuator plate or disk 84translationally slidable left-right as shown at arrow 86 along housing88 to vary the size of nozzle orifices such as 90, 92, as elongatedslots or openings 94, 96 of disk 84 moved therealong. Slots or openings94, 96 may have a frustoconical taper 98 to enhance the noted venturiacceleration effect. As disk 84 moves leftwardly in FIG. 3, the size ofventuri orifices 90, 92 increases, i.e. leftward movement of actuatordisk 84 expands the size of orifices 90, 92 along a cross-sectional areathereof transverse to axial flow direction 58, to vary the size of theorifices. Rightward movement of actuator disk 84 restricts orifices 90,92 along the cross-sectional area thereof transverse to axial flowdirection 58. Alternatively, or additionally, leftward movement ofactuator disk 84 may open additional orifices, and rightward movement ofactuator disk 84 may close some orifices, to vary the number of orificesthrough which the gas-liquid stream flows.

FIG. 4 shows another embodiment having an actuator disk 100 rotatableabout a rotation axis 102 parallel to axial flow direction 58. Actuatordisk 100 is rotatable clockwise as shown at arrow 104 about axis 102 torestrict and/or close one or more nozzle orifices 106, 108, etc., ofhousing wall 110, as slots 112, 114 in actuator disk 100 slidetransversely thereacross.

FIGS. 5-10 show a preferred implementation of the embodiment of FIG. 4.Housing 120 has an inlet 122, comparable to inlet 42, FIG. 1, forreceiving the gas-liquid stream 32, e.g. from crankcase 36. Housing 120has an outlet 124, comparable to outlet 44, FIG. 1, for discharging gasstream 46, e.g. to air intake manifold 38. Housing 120 has a drain 126,comparable to drain 45, FIG. 1, draining separated fluid 47 fromimpactor collector 54, e.g. returning collected oil droplets at 47 tocrankcase 36. Actuator disk 100 is rotationally mounted to housingspindle 128 to rotate about axis 102. Disk 100 is connected by link 130to diaphragm plate 132 having legs 134 extending through diaphragm 136and mounted on the opposite side to spring plate 138, such thatdiaphragm 136 is sandwiched between plates 132 and 138. Biasing spring140 bears between spring plate 138 and closure cap 142 mounted to thehousing and sealed thereto at perimeter 144 and providing a firstchamber 146 on one side of the diaphragm, and a second chamber 148 onthe other side of the diaphragm.

FIG. 9 shows a low pressure condition of the gas-liquid flow stream 32,with actuator disk 100 rotated clockwise as shown at arrow 150 to afirst position minimizing cumulative flow through the plurality ofnozzle orifices 106, 108, etc., for example restricting the size of oneor more such orifices and/or closing one or more of such orifices. FIG.10 shows a higher pressure condition of gas-liquid flow stream 32, withactuator disk 100 rotated counterclockwise as shown at arrow 152 to asecond position maximizing cumulative flow through the plurality ofnozzle orifices 106, 108, etc., e.g. by expanding one or more of suchorifices and/or opening one or more of such orifices. The actuator has aplurality of positions between its minimum and maximum cumulative flowpositions in response to pressure of the gas-liquid stream to maintainthe pressure constant, i.e. maintain a constant ΔP relative to a givenreference. The given reference may be atmospheric pressure, for exampleas provided by one or more vent openings 154, 156 in end cap 142communicating with chamber 148.

In the embodiment of FIGS. 5-10, the noted pressure sensor is providedby diaphragm 136 having first and second opposite sides 158 and 160,with the first side 158 coupled through plate 132 and link 130 toactuator disk 100, comparably to diaphragm 70, FIG. 1, having first andsecond opposite sides 69 and 71, with first side 69 coupled through link72 to actuator disk 62. One of the first and second sides of thediaphragm is exposed to pressure in the gas-liquid stream 32 to controlmovement of the actuator. In FIGS. 1 and 9, the noted first side 69, 158of the respective diaphragm 70, 136 is exposed to pressure in thegas-liquid stream to control movement of the actuator. In otherembodiments, to be described, the second side of the diaphragm isexposed to pressure in the gas-liquid stream to control movement of theactuator. In FIGS. 1-2 and 5-10, the biasing member 76, 140 is overcomeby a given pressure in gas-liquid stream 32 in respective chamber 74,146 on respective first side 69, 158 of respective diaphragm 70, 136.

FIG. 11 shows another embodiment having an actuator disk 161 rotatableabout rotation axis 102 parallel to axial flow direction 58. Actuatordisk 161 is rotationally mounted on housing plate 162 at spindle 163 andis rotational to open or close one or more nozzle orifices such as 164,165, etc. Upon rotation of disk 161 as shown at arrow 166, one or moreradial arms 167, 168 of the disk, which may have differing arcuatelengths, open or close respective nozzle orifices, to thus vary thenoted cumulative flow through the nozzle structure by varying the numberof nozzle orifices available for flow therethrough.

FIG. 12 shows another embodiment having an actuator disk 170translational along a direction parallel to axial flow direction 58.Actuator 170 is movable from solid line position 172 to dashed lineposition 174 along arrow 176 in the same direction as axial flowdirection 58 to decrease the noted cumulative flow of the gas-liquidstream by restricting or closing nozzle orifices such 178 in housingwall 180. Actuator 170 is movable from dashed line position 174 to solidline position 172 as shown at arrow 182 in the opposite direction toaxial flow direction 58, to increase the noted cumulative flow. Theactuator includes valve stems such as 184 having respective conicallyshaped valve heads such as 186 engageable with respective valve seatsprovided by the nozzle orifices such as 178. The valve head 186 isconically shaped along a taper which narrows toward a direction pointingin the same direction as axial flow direction 58. The valve seats may beconically shaped complementally to the valve heads. In an open valvecondition as shown in solid line at 172, the gas-liquid stream flows asshown at 188, 190 through nozzle orifice 178 and strikes impactionsurface 60, which may be the facing surface of actuator 170 or may beprovided by an impactor collector such as 54 mounted thereto, causingliquid particle separation as above.

FIGS. 13-18 show a preferred implementation of the embodiment of FIG.12. Housing 200 has an inlet 202, comparable to inlet 42, FIG. 1, forreceiving the gas-liquid stream 32, e.g. from crankcase 36. Housing 200has an outlet 204, comparable to outlet 44, FIG. 1, for discharging gasstream 46, e.g. to air intake manifold 38. Housing 200 has a drain 206,comparable to drain 45, FIG. 1, draining separated fluid 47 fromimpactor collector 54, e.g. returning collected oil droplets at 47 tocrankcase 36. Inner housing wall 180 has a plurality of nozzle orifices178, 208, etc. Actuator disk 170 has a plurality of valve stems 184,210, etc. having respective valve heads 186, 212, etc. opening andclosing and/or restricting and expanding respective nozzle orifices 178,208, etc. Actuator disk 170 is mounted on diaphragm 214 which is sealedat its periphery 216 in the housing. The housing includes a chamber 218receiving the gas-liquid stream from inlet 202, a subchamber 220 betweeninner housing wall 180 and first side 222 of diaphragm 214, and achamber 224 on the second side 226 of the diaphragm. The housing isclosed by a first closure cap 228 enclosing chamber 218, and a secondclosure cap 230 enclosing chamber 224.

The gas-liquid stream 32 flows through housing inlet 202 into chamber218 between closure cap 228 and inner housing wall 180. Subchamber 220is between inner housing wall 180 and diaphragm 214 and receives thegas-liquid flow stream communicated through nozzle orifices 178, 208,etc., when open. Chamber 224 is between closure cap 230 and the notedsecond side 226 of diaphragm 214 and includes a spacer ring 232 having aplurality of spacer legs 234 for providing a plenum in chamber 224. Aplurality of communication passages 236, 238, etc. provide communicationof gas-liquid flow stream pressure therethrough as shown at arrows 240,242, etc. from chamber 218 into chamber 224 as shown at arrows 244, 246,etc. The size and number of communication passages 236, 238, etc. areselected such that the ratio of pressure on second side 226 of diaphragm214 resulting from and relative to the pressure of the gas-liquid streamis greater than the ratio of the pressure on first side 222 of diaphragm214 relative to and resulting from the pressure of the gas-liquidstream. Diaphragm 214 is inherently biased, or alternatively has anon-stretched position, as shown in FIG. 13, with nozzle orifices 178,208, etc. closed by valve heads 186, 212, etc., which is the dashed lineposition 174 shown in FIG. 12. This inherent bias or non-stretchedposition of the diaphragm has a bias toward such closed position of thenozzle orifices which is greater than the pressure in chamber 224 onsecond side 226 of the diaphragm, e.g. at low engine speed. As thepressure of the gas-liquid stream increases, the pressure in chamber 224on second side 226 of the diaphragm increases and overcomes the inherentbias of diaphragm 214 to stretch and move the diaphragm to the positionshown in FIG. 14, which is the solid line position 172 in FIG. 12, tobegin to open nozzle orifices 178, 208, by moving valve heads 186, 212,etc. away from their respective valve seats along direction 182, FIG.12. This opening movement of the valves is opposed and counterbalancedby the pressure in subchamber 220 on first side 222 of the diaphragm nowavailable due to the gas-liquid stream flow as shown at arrows 188, 190through the respective nozzle orifices into subchamber 220. The notedratio of pressures on the first and second sides of the diaphragmcontrol the opening and closing of the valves, and vary the size of thenozzle orifices, and if desired the number of orifices opened or closed.

The cumulative flow through the nozzles is varied by variable flowactuator 170 wherein movement of such actuator varies at least one ofthe size and number of orifices 178, 208, etc. The cumulative flow mayfurther be varied by varying: the axial height of valve stems 184, 210,etc. stem-to-stem; the taper, width, etc. of valve heads 186, 212, etc.from head-to-head; the size of the orifices 178, 208, etc.; the pressureratio on opposite sides 222 and 226 of the diaphragm by varying the sizeand number of communication passages 236, 238; and various combinationsthereof.

Actuator 170 has a first position as shown in FIG. 13 and in dashed line174 in FIG. 12, minimizing or closingly stopping cumulative flow of thegas-liquid stream through the plurality of nozzle orifices 178, 208. Theactuator has a second position as shown in FIG. 14 and in solid line 172in FIG. 12, maximizing cumulative flow through the plurality of nozzleorifices 178, 208, etc. Actuator 170 is moved by the pressure sensorprovided by diaphragm 214 between the noted first and second positionsand a plurality of positions therebetween in response to pressure of thegas-liquid stream to maintain such pressure constant, i.e. maintain aconstant ΔP if desired. As above, this overcomes prior trade-offs in afixed separator which is non-adaptive to changing engine or flowconditions nor different engine sizes. Side 226 of the diaphragm isexposed to pressure in the gas-liquid stream in both of the noted firstand second positions of the actuator and the intermediate positionstherebetween. Side 222 of the diaphragm is exposed to pressure in thegas-liquid stream in the noted second position and intermediatepositions of the actuator.

FIG. 19 shows a further embodiment, with an actuator 250 translationalalong a direction 252 parallel to axial flow direction 58, comparably toactuator 170, FIG. 12, for opening and closing, and/or enlarging andrestricting nozzle orifices such as 254, 256, etc. in housing wall 258.Actuator 250 has a plurality of valve stems 260, 262, etc. havingconically shaped valve heads 264, 266, etc., engageable with respectivevalve seats such as 268, 270, etc. which valve seats may be conicallyshaped complementally to the valve heads. Unlike FIG. 12, valve heads264, 266 in FIG. 19 are conically shaped along a taper which narrowstoward a direction pointing opposite to axial flow direction 58.Variable flow actuator 250 varies the cumulative flow of the gas-liquidflow stream through nozzle orifices 254, 256, etc. in response to agiven parameter, by moving back and forth as shown at arrow 252. Ifpressure in the gas-liquid flow stream is the designated parameter, thepressure against valve heads 264, 266 may be used to open the valves,and the pressure against such valve heads and surface 272 of theactuator disk may be used to vary and expand the cumulative flow area byincreasing the cross-sectional area of the nozzle orifices. A biasingspring such as 76, 140 may bear against surface 274 of the actuator diskto bias the actuator to a closed or restricted position. Actuator 250moves in the same direction as axial flow direction 58 to increase thenoted cumulative flow, and moves in the opposite direction to axial flowdirection 58 to decrease the noted cumulative flow.

FIGS. 20-22 show a further embodiment having a plurality of actuatorassemblies 280, 282, 284, 286 in housing 290. In actuator assembly 280,housing sub-wall 292 has a plurality of nozzle orifices such as 294,296, 298, etc. through which the gas-liquid flow stream at 58 isaccelerated and strikes inertial impactor collector 54 at impactionsurface 60, as above, causing liquid particle separation from thegas-liquid stream. Impactor collector 54 is mounted on variable flowactuator 300, or alternatively face surface 302 of the actuator mayprovide the impaction surface 60. Actuator 300 is translational back andforth as shown at arrow 304 along a direction parallel to axial flowdirection 58, and is biased to a closed position (upwardly in FIG. 22),by a spring 306 bearing between underside 308 of actuator disk 300 and aspring seat 310 of the housing. In the upwardly biased closed positionshown in FIG. 22, an annular gasket 312 on the outer circumference ofactuator disk 300 engages the lower apex of V-shaped valve seat 314 ofthe housing in sealing relation to block gas stream and liquid streamflow therepast. Actuator 300 is movable in a second direction(downwardly in FIG. 22) to a second open position wherein gasket 312 ismoved downwardly away from and disengaged from valve seat 314 by a gaptherebetween to permit gas stream flow therepast to the housing outlet,shown schematically at 44 in FIG. 22, and to permit liquid stream flowtherepast to the housing drain, shown schematically at 45 in FIG. 22.The remaining actuator assemblies 282, 284, 286 are the same.

The inertial impactor collector of the above embodiments of FIGS. 1-19is provided in FIGS. 20-22 as a plurality of impaction surfaces 60, 60a, 60 b, 60 c each receiving the gas-liquid stream through a respectiveset of one or more orifices 294, 296, 298, etc. The variable flowactuator is provided by a plurality of impaction buttons 300, 300 a, 300b, 300 c each carrying a respective impaction surface 60, 60 a, 60 b, 60c. Each impaction button is movable between the noted closed and openpositions independently of the other impaction buttons. The notedcumulative flow of the gas-liquid stream at 58 is varied by varying thenumber of impaction buttons in at least one of the closed and openpositions. For example, cumulative flow may be increased by opening oneor more of the impaction buttons, and decreased by closing one or moreimpaction buttons. The impaction buttons are spring biased at differentspring rates, to provide differential sequential opening and closingthereof. For example, each of springs 306, 306 a, 306 b, 306 c has adifferent spring rate, such that, for example, impaction button 300opens first in response to increasing pressure, and then impactionbutton 300 a opens in response to further increasing pressure, and thenimpaction button 300 b opens in response to yet further increasingpressure, and so on. Impaction buttons 300, 300 a, 300 b, 300 c aretranslational along a direction parallel to axial flow direction 58, andare biased to the noted closed position (upwardly in FIG. 20) along thenoted direction parallel to axial flow direction 58.

Referring to FIG. 1, gas-liquid stream 32 becomes gas stream 46 andflows from upstream to downstream through the housing from inlet 42 thenthrough nozzle orifices 50, 52, etc. then to inertial impactor collector54 at impaction surface 60 then to outlet 44. In the embodiments ofFIGS. 1-19, the noted actuator is upstream of the inertial impactorcollector. In the embodiment of FIGS. 20-22, the actuator is downstreamof the inertial impactor collector.

Present Application

FIG. 23 shows an inertial gas-liquid separator 320 for removing liquidparticles from a gas-liquid stream. A housing 322 has an inlet 324 forreceiving a gas-liquid stream 326, and an outlet 328 for discharging agas stream 330. Nozzle structure 332 in the housing includes a pluralityof nozzles such as 334 receiving the gas-liquid stream from inlet 324and accelerating the gas-liquid stream through the nozzles. An inertialimpactor collector 336 is provided in the housing in the path of theaccelerated gas-liquid stream and causes liquid particle separation fromthe gas-liquid stream, followed by flow of the gas stream as shown at338, and drainage of liquid 340 at drain 342. A variable flow actuator344 is movable, e.g. up and down in FIG. 23, to open and close avariable number of nozzles 334.

Variable flow actuator 344 is responsive to pressure of gas-liquidstream 326. The variable flow actuator responds to increasing pressureby moving, e.g. upwardly in FIG. 23, to open more of nozzles 334. Thevariable flow actuator responds to decreasing pressure to close more ofnozzles 334, e.g. by moving downwardly in FIG. 23. In this manner, asubstantially constant pressure drop is maintained across inertialgas-liquid separator 320 between inlet 324 and outlet 328notwithstanding changing flow conditions of the gas-liquid streamtherethrough. It is preferred that the distance between nozzles 334 andinertial compactor collector 336 be constant and unchanged by movementof variable flow actuator 344.

In FIG. 23, variable flow actuator 344 is provided by a piston 346axially slidable along a cylinder 348 extending along an axis 350. Thecylinder has cylinder wall 352 with a plurality of apertures 354therethrough providing the noted plurality of nozzles. The apertures arecovered and uncovered by piston 346 during sliding of the piston alongthe cylinder to respectively close and open the nozzles. Inertialimpactor 336 is an annular member spaced radially outwardly of cylinder348 by an annular acceleration gap 356 therebetween. Apertures 354extend radially through cylinder wall 352. Gas-liquid stream 326 flowsaxially within cylinder 348 and then radially outwardly throughapertures 354 uncovered by piston 346 and is accelerated into annularacceleration gap 356 and impact inertial impactor collector 336 causingliquid particle separation from the gas-liquid stream. Gas-liquid stream326 flows in a given axial direction within cylinder 348, e.g. upwardlyin FIG. 23. After the noted separation, the gas stream at 338 flows inthe same given axial direction along the exterior of cylinder 348. Thegas-liquid stream flows through inlet 324 in the noted given axialdirection. The gas stream at 330 flows through outlet 328 in the samenoted given axial direction.

Piston 346 has a leading surface 358 facing the incoming flow of thegas-liquid stream 326 thereagainst. Leading surface 358 is configured todirectionally guide and direct flow to apertures 354 in cylinder wall352. In one embodiment, such directional configuration is a cone shapeor a convex shape or a channeled guide surface, etc.

In the embodiment of FIG. 23, piston 346 is a gravimetric piston relyingon the weight of the piston to regulate flow. The noted axis of movementis vertical. Piston 346 has the noted bottom face 358 facing downwardlyand receiving the incoming flow of the gas-liquid stream 326thereagainst. Piston 346 slides upwardly in cylinder 348 in response toincreasing pressure of the gas-liquid stream 326 to open up more ofapertures 354. The piston slides downwardly in the cylinder in responseto decreasing pressure of the gas-liquid stream 326 to close off more ofapertures 354. The top of the cylinder includes a vent hole 360 to avoidcreation of a vacuum within the cylinder during piston movement, so asnot to impede movement of the piston.

FIG. 24 shows another embodiment and uses like reference numerals fromabove where appropriate to facilitate understanding. A biasing member,such as spring 362, biases piston 346 a against the incoming flow ofgas-liquid stream 326 thereagainst. Piston 346 a slides in a first axialdirection, e.g. upwardly in FIG. 24, against the bias of biasing spring362 in response to increasing pressure of gas-liquid stream 326 to openmore of apertures 354. Piston 346 a slides in a second oppositedirection, e.g. downwardly in FIG. 24, as biased by biasing spring 362in response to decreasing pressure of gas-liquid stream 326 to close offmore of apertures 354.

FIG. 25 shows another embodiment of an inertial gas-liquid separator 370for removing liquid particles from a gas-liquid stream. A housing 372has an inlet 374 for receiving a gas-liquid stream 376, and has anoutlet 378 for discharging a gas stream 380. Nozzle structure 382 in thehousing has a plurality of nozzles 384 receiving the gas-liquid streamfrom inlet 374 and accelerating the gas-liquid stream through thenozzles. An inertial impactor collector 386 is provided in the housing,which may be an interior wall of the housing, in the path of theaccelerated gas-liquid stream. A variable flow actuator 388 in thehousing is movable to open and close a variable number of nozzles 384.

Housing 372 has a wall 390 facing inertial impactor collector 386 andseparated therefrom by an annular acceleration gap 392 therebetween.Wall 390 has a plurality of apertures 394 therethrough providing thenoted nozzles 384. Variable flow actuator 388 is provided by a rollingdiaphragm 396 having a resilient flexible region 398 covering anduncovering apertures 394 in a flexing motion to respectively close andopen nozzles 384. Diaphragm 396 has a first side 400 communicating withinlet 374 and exposed to the incoming flow of the gas-liquid stream 376.The diaphragm has a second opposite side 402 communicating with outlet378. First side 400 of the diaphragm has a changing effective area,which effective area is defined as the area exposed to incoming flow.The effective area of the diaphragm increases in response to increasingpressure of gas-liquid stream 376, and the diaphragm uncovers and opensup more of apertures 394. The effective area of the diaphragm decreasesin response to decreasing pressure of gas-liquid stream 376, and thediaphragm covers and closes off more of apertures 394. Wall 390 is acylindrical wall of a cylinder 404 in the housing and extending axiallyalong axis 406. Apertures 394 extend radially through cylinder wall 390.Diaphragm 396 has an outer portion 408 extending axially along theinterior of cylinder wall 390 and is flexible radially away therefrom touncover and open more of the apertures 394. Diaphragm 400 has a centralportion 410 spanning radially inwardly from the outer portion andmovable in a first axial direction, e.g. downwardly in FIG. 25, to flexouter portion 408 of the diaphragm radially inwardly away from apertures394 and out of engagement of cylinder wall 390 to uncover and open moreof the apertures. Central portion 410 is movable in a second oppositeaxial direction, e.g. upwardly in FIG. 25, to flex outer portion 408 ofthe diaphragm radially outwardly toward apertures 394 and intoengagement with cylinder wall 390 to cover and close off more of theapertures 394. Biasing spring 412 biases central portion 410 of thediaphragm in the noted second axial direction, e.g. upwardly in FIG. 25,and against the incoming flow of gas-liquid stream 376. The separatedliquid drains as shown at arrow 414 at drain 416. The gas stream flowsas shown at arrows 418 to outlet 378. A central column 420 supports anupper sleeve 422 in telescopic axial sliding relation which in turnsupports upper central portion 410 of the diaphragm. The base of supportcolumn 420 has a plurality of slots or apertures 424 passing the gasflow therethrough to outlet 378.

FIG. 26 shows another embodiment of an inertial gas-liquid separator 430for removing liquid particles from a gas-liquid stream. Housing 432 hasan inlet 434 for receiving a gas-liquid stream 436, and has an outlet438 for discharging a gas stream 440. Nozzle structure 442 in thehousing has a plurality of nozzles 444 receiving the gas-liquid streamfrom inlet 434 and accelerating the gas-liquid stream through nozzles444. An inertial impactor collector 446 is provided in the housing inthe path of the accelerated gas-liquid stream and causes liquid particleseparation from the gas-liquid stream. The liquid drains as shown atarrow 448 at drain 450. The gas stream continues as shown at arrows 452,454 to outlet 438. A variable flow actuator 456 is movable to open andclose a variable number of nozzles 444. The housing has a wall 458facing inertial impactor collector 446 and separated therefrom by anacceleration gap 460 therebetween. Wall 458 has a plurality of apertures462 therethrough providing the noted nozzles. Variable flow actuator 456is provided by a rolling diaphragm 464 having a resilient flexibleregion 466 covering and uncovering apertures 462 in a flexing motion torespectively close and open the nozzles. Diaphragm 464 has a first side468 communicating with inlet 434 and exposed to the incoming flow ofgas-liquid stream 436. The diaphragm has a second opposite side 470communicating with outlet 438. First side 468 of the diaphragm has achanging effective area, such effective area being defined as the areaexposed to incoming flow. The effective area of the diaphragm increasesin response to increasing pressure of gas-liquid stream 436, and thediaphragm uncovers and opens more of apertures 462. The effective areaof the diaphragm decreases in response to decreasing pressure ofgas-liquid stream 436, and the diaphragm covers and closes off more ofapertures 462.

Wall 458 is a plate having an incoming flow opening 472 therethroughcommunicating with inlet 434 and receiving the incoming flow ofgas-liquid stream 436. The incoming flow flows axially along axis 474through opening 472. Plate 458 extends laterally outwardly from opening472. The plurality of apertures 462 extend axially through plate 458 andare laterally outward of opening 472. Diaphragm 464 has an outer portion476 extending laterally along plate 458 and flexible axially, e.g.upwardly in FIG. 26, away therefrom to uncover and open up more ofapertures 462. Diaphragm 464 has a central portion 478 spanninglaterally inwardly from the outer portion and movable in a first axialdirection, e.g. upwardly in FIG. 26, to flex outer portion 476 of thediaphragm axially away from apertures 462 and out of engagement of plate458 to uncover and open up more of apertures 462. Central portion 478 ofthe diaphragm is movable in a second opposite axial direction, e.g.downwardly in FIG. 26, to flex outer portion 476 of the diaphragmaxially toward apertures 462 and into engagement with plate 458 to coverand close off more of apertures 462. A biasing spring 480 biases centralportion 478 of the diaphragm in the noted second axial direction, e.g.downwardly in FIG. 26, and against the incoming flow of gas-liquidstream 436. The gas-liquid stream 436 flows through opening 472 in thenoted first axial direction, e.g. upwardly in FIG. 26, and then flows asshown at arrows 482 in the noted second axial direction, e.g. downwardlyin FIG. 26. The gas stream flows from acceleration gap 460 as shown atarrows 452, 454 to outlet 440 in the noted first axial direction.

In the above noted embodiments, the system automatically adapts thenumber or size of apertures to the flow, to keep restriction as constantas possible. This is desirable, particularly in internal combustionengine applications in a truck in a braking mode. In other applications,a change in hole or aperture area is done step by step at extendedintervals, for example manually at service intervals for the vehicle,particularly when crankcase pressure reaches a predetermined level. Inone example, piston 346, FIG. 23, can be manually changed betweendifferent positions at service intervals and retained by a retainer suchas a detent, latch, finger in slot, or the like, in a fixed axialposition until the next further service interval, at which the servicetechnician will determine if the piston should be moved to a differentaxial position to cover or uncover more or less apertures 354 until thenext service interval, and so on. In another example, the disks such as84 of FIG. 3 or 100 of FIG. 4 may be fixed in place at a serviceinterval and remain so fixed until the next service interval, at whichtime they may be adjusted and moved by the service technician, andremain so adjusted until a subsequent service interval, and so on. Inanother example, a pair of disks may be provided which can be angularlyrotated or slid relative to each other and locked in position, with aseries of detents or clicks, with gradations indicating to the servicetechnician a given setting corresponding to a given crankcase pressurereading. The mechanic will then manually slide or rotate a disk or othervariable actuator to a given set position, to accommodate wear since thelast service interval and to correspond to a current crankcase pressurereading as the engine ages.

It is recognized that various equivalents, alternatives andmodifications are possible within the scope of the appended claims. Theinvention is particularly useful in closed crankcase ventilation (CCV)and open crankcase ventilation (OCV) applications, though it may be usedin various other inertial gas-liquid impactor separator applications forremoving liquid particles from a gas-liquid stream.

1-21. (canceled)
 22. An apparatus for removing oil particles in a flowfrom a crankcase responsive to changing flow conditions, comprising: acylindrical wall defining a first flow path extending along an axis, thefirst flow path being fluidly connected to an inlet, the wall furtherdefining a plurality of radially extending apertures, the radiallyextending apertures defining a second flow path toward an impactor wall,wherein the impactor wall is spaced apart from the cylindrical wall byan annular gap, the annular gap defining a third flow path that isfluidly connected to an outlet; and, a variable flow actuator thattranslates axially within the first flow path between a first positionand at least a second position, wherein movement of the actuator fromthe first position to the second position increases at least one of sizeand number of the radially extending apertures fluidly connecting thefirst flow path to the third flow path.
 23. The apparatus of claim 22,wherein movement of the actuator from the first position to the secondposition increases number of the radially extending apertures.
 24. Theapparatus of claim 23, wherein the impactor wall includes a rough porouscollection surface.
 25. The apparatus of claim 24, wherein thecollection surface is a fibrous covering.
 26. The apparatus of claim 25,wherein the actuator is in the first position in a low pressure flowcondition and the actuator translates toward the second position in ahigher pressure flow condition.
 27. The apparatus of claim 26, furthercomprising a spring positioned to bias the variable flow actuator towardthe first position.
 28. The apparatus of claim 26, further comprising anoil drain fluidly connected to the third flow path, the drain being at alower level than the impactor wall.
 29. An oil-mist inertial separatorfor combustion blow-by gases from a crankcase of an engine, comprising:an inlet fluidly connected to an axial flow section defined by aninterior of a cylindrical wall, the wall defining a plurality of nozzleorifices extending radially therethrough; an impactor collector spacedapart from an exterior of the cylindrical wall by a gap, the gap being asecond flow section fluidly connected to the axial flow section by thenozzle orifices, the gap also being fluidly connected to an outlet; avariable flow actuator positioned within the axial flow section andmoving axially between a low flow condition and a high flow condition,wherein the actuator moves 10 axially to maintain flow speed through thenozzle orifices at values that are relatively constant by varying atotal cross-section defined by the plurality of nozzle orifices.
 30. Theoil-mist separator of claim 29, wherein the actuator moves axially awayfrom the inlet to increase the total cross-section defined by theplurality of nozzle orifices.
 31. The oil-mist separator of claim 30,wherein the total cross-section is increased by movement of the actuatorthat uncovers at least one additional nozzle orifice.
 32. The oil-mistseparator of claim 33, wherein the total cross-section is increased bymovement of the actuator that uncovers additional cross-section of atleast one of the plurality of nozzle orifices.
 33. The oil-mistseparator of claim 31, wherein the impactor wall includes a porousfibrous collection surface.
 34. The oil-mist separator of claim 33,further comprising a spring positioned to bias the variable flowactuator toward the low flow condition axial position.
 35. A method ofseparating oil particles from an oil-gas mixture vented from a crankcaseof an engine that is responsive to changing flow conditions, comprisingthe steps of: passing the mixture through a cylindrical flow pathextending along a first axis; redirecting the flow through a turn into aplurality of nozzles extending radially through a wall defining thecylindrical flow path toward a fibrous covered inertial impactor surfacespaced apart from the wall by an annular gap; redirecting the flowthrough a sharp directional turn to flow along the annular gap that isfluidly connected to an outlet; shifting a variable flow actuatoraxially in the cylindrical flow path from a low flow condition toward ahigher flow condition when pressure of the flow increases, whereinshifting the variable flow actuator from the low flow condition to thehigher flow condition increases at least one of a total number of thenozzles fluidly connecting the cylindrical flow path to the annular gapor a cross-section of at least one of the nozzles fluidly connecting thecylindrical flow path to the annular gap.
 36. The method of claim 35,wherein shifting the variable flow actuator increases at least one of atotal number of the nozzles fluidly connecting the cylindrical flow pathto the annular gap.
 37. The method of claim 35, further comprising usinga spring to bias the variable flow actuator toward the low flowcondition.
 38. A method of reducing oil content in combustion blow-bygases from a crankcase of an engine that is responsive to changingengine conditions, comprising the steps of: passing the combustionblow-by gases through a first axial flow path defined by an interior ofa wall; redirecting the combustion blow-by gases to flow into aplurality of nozzle orifices extending radially through the wall toaccelerate the gases to flow across an annular gap into an inertialimpactor collector at least partially covered by a fibrous material;translating a variable flow actuator along the first axial flow path tomaintain flow speed through the nozzle orifices at values that arerelatively constant by varying total cross-section of the plurality ofnozzle orifices.
 39. The method of claim 38, wherein the totalcross-section is increased by movement of the actuator that uncovers atleast one additional nozzle orifice.